Generally, semiconductor devices are manufactured by depositing many different types of material layers over a semiconductor workpiece or wafer. The material layers are patterned using lithography. The material layers typically comprise thin films of conductive, semiconductive, and insulating materials that are patterned and etched to form integrated circuits (IC's).
For many years in the semiconductor industry, silicon dioxide (SiO2), which typically has a dielectric constant (k) of about 3.9, was often used as an insulating material between conductive features of semiconductor devices. However, as the demand for smaller and faster circuits has continued to drive the need for smaller feature sizes and denser circuitry, lower dielectric constant insulating materials are being used for insulating material layers of integrated circuits, which have a dielectric constant of less than 3.9.
Low dielectric constant insulating materials often comprise porous materials that permit substances and materials to permeate through the insulating materials, which can result in a loss of insulating properties of the material and other problems from contamination. Photoresist or resist is a photosensitive material used in lithography that is used as a mask to pattern material layers of semiconductor devices. Some substances can pass through low dielectric constant insulating materials and result in a problem referred to as “resist poisoning,” which can occur during a patterning process, e.g., during lithography. If certain substances or materials permeate through the porous low dielectric constant insulating material, damage can be caused to the photoresist, resulting in an inaccurate pattern transfer.
Thus, what are needed in the art are improved integration schemes for the patterning of low dielectric constant insulating materials in semiconductor device manufacturing.